Folding knife



FIG. 1 is a perspective view of a folding knife showing my new design;

FIG. 2 is a front elevation view thereof;

FIG. 3 is a rear elevation view thereof;

FIG. 4 is a left side elevation view thereof;

FIG. 5 is a right side elevation view thereof;

FIG. 6 is a top plan view thereof;

FIG. 7 is a bottom plan view thereof; and,

FIG. 8 is another perspective view thereof, showing the folding knife in a folded state of use.

The broken lines depict portions of the folding knife in which the design is embodied that form no part of the claimed design. 

CLAIM The ornamental design for a folding knife, as shown and described. 